Temperature-controlled flange and reactor system including same

ABSTRACT

A flange, flange assembly, and reactor system including the flange and flange assembly are disclosed. An exemplary flange assembly includes heated and cooled sections to independently control temperatures of sections of the flange. Methods of using the flange, flange assembly and reactor system are also disclosed.

FIELD OF DISCLOSURE

The present disclosure generally relates to gas-phase reactors andsystems. More particularly, the disclosure relates to flanges forgas-phase reactors, to reactor systems including one or more of theflanges, and to methods of using the same.

BACKGROUND OF THE DISCLOSURE

Gas-phase reactors, such as chemical vapor deposition (CVD),plasma-enhanced CVD (PECVD), atomic layer deposition (ALD), and thelike, can be used for a variety of applications, including depositingand etching materials on a substrate surface. For example, gas-phasereactors can be used to deposit and/or etch layers on a substrate toform semiconductor devices, flat panel display devices, photovoltaicdevices, microelectromechanical systems (MEMS), and the like.

A typical gas-phase reactor system includes a reactor including areaction chamber, one or more precursor gas sources fluidly coupled tothe reaction chamber, one or more carrier and/or purge gas sourcesfluidly coupled to the reaction chamber, and a vacuum source. In somecases, a reaction chamber can be formed of quartz or similar material.In these cases, the gas-phase reactor system often includes one or more(e.g., metal) flanges to couple the reaction chamber to other reactorsystem components. For example, reactor systems can include a firstflange to fluidly couple the one or more precursor gas sources to thereaction chamber and a second flange to couple the outlet of thereaction chamber to the vacuum source. The first and second flanges canbe sealably coupled to the reaction chamber using a resilient seal, suchas an O-ring.

Various reactors may desirably run at elevated temperatures to obtaindesired reactions within the reaction chamber, and particularly on ornear a surface of a substrate. For example, gas-phase reactors can oftenoperate at temperatures of up to 200° C. However, such elevatedtemperature may deleteriously affect (e.g., cause deterioration of) theresilient seal used to couple the first or second flange to the reactionchamber and/or other reactor system components. Such deterioration canresult in gas leakage. However, if the temperature of the flange isintentionally reduced, relative to the operating temperature of thereaction chamber during substrate processing to protect the resilientseal, the precursors and/or reaction byproducts can react with and/orcondense onto a surface of the flange, creating materials that cangenerate particles on the substrates during processing and/or that maybe hazardous. This problem may become even more pronounced when usingprecursors that originate as a liquid or solid.

Accordingly, improved temperature-controlled flanges and reactor systemsincluding such flanges are desired.

SUMMARY OF THE DISCLOSURE

Various embodiments of the present disclosure relate to flanges, flangeassemblies, reactor systems including the flanges and flange assemblies,and to methods of using the same. While the ways in which variousembodiments of the present disclosure address drawbacks of priorflanges, flange assemblies, and reactor systems are discussed in moredetail below, in general, various embodiments of the disclosure provideflanges and flange assemblies, wherein a portion or section of theflange can be heated and another portion or section of the flange can becooled. For example, sections of the flange near a sealing member (e.g.,a resilient seal) can be cooled to mitigate degradation of the seal thatwould otherwise occur from elevated processing temperatures and othersections of the flange can be heated to mitigate condensation ofprecursors and/or byproducts on the flange.

In accordance with at least one exemplary embodiment of the disclosure,a flange includes a first surface for coupling to a reactor, an opposingsecond surface, an opening between the first surface and the secondsurface, at least one recess to receive a heater, and at least onecooling channel. The flange can be attached to a first or front end ofthe reaction chamber, in which case the opening can be configured toreceive one or more substrates and/or one or more precursors orreactants. Alternatively, the flange can be attached to a second or backend of the reaction chamber, and the opening can be configured to allowgases to flow toward an exhaust. The flange can additionally include arecess on the first surface and/or the second surface to receive asealing member, such as a resilient seal (e.g., an O-ring). The at leastone cooling channel can be proximate the recess on the first surfaceand/or the second surface to receive the sealing member—e.g., to preventa sealing member from reaching undesirably high temperatures duringsubstrate processing. The at least one recess to receive a heater can beplaced further away from the recess on the first surface and/or thesecond surface to receive a sealing member, to provide heat to theflange—e.g., to mitigate condensation of process gasses thereon, whilemitigating added heat proximate the recess on the first surface and/orthe second surface to receive the sealing member.

In accordance with at least one other embodiment of the of thedisclosure, a flange assembly includes a flange, such as a flangedescribed above and elsewhere herein, at least one heater, and at leastone cooling channel. In accordance with various aspects of theseembodiments, the at least one heater is embedded within the flange—e.g.,the heater can be disposed within a recess in the flange to receive theheater. As set forth in more detail below, exemplary flanges can includea plurality of heaters embedded within the flange to provide heat tomultiple sections of the flange. The heater(s) can be held in placewithin the flange by a heater retainer. Similarly, the at least coolingchannel can be embedded within the flange. Exemplary flanges can includemultiple cooling channels. Each cooling channel can include one or moretubes (e.g., pipes). In accordance with at least some examples of theseembodiments, the flange assembly includes one or more thermocouples thatmay be embedded within the flange. Exemplary flange assemblies canfurther include a cover plate. As described in more detail below,various flange assemblies can be configured to couple to a first end ora second end of a reaction chamber.

In accordance with further exemplary embodiments of the disclosure, areactor system includes a flange and/or a flange assembly as describedherein. The reactor system can additionally include one or more reactionchambers, one or more gas manifolds, one or more precursor sources, oneor more vacuum sources, one or more robotic transfer arms, and/or thelike.

In accordance with yet additional exemplary embodiments of thedisclosure, a method of processing a substrate includes providing aflange, flange assembly, and/or reactor system as described herein andcooling and/or heating at least one flange or portion(s) thereof. Inaccordance with at least some aspects of these embodiments, at least onesection of the flange is heated and at least one other section of theflange is cooled.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

A more complete understanding of exemplary embodiments of the presentdisclosure can be derived by referring to the detailed description andclaims when considered in connection with the following illustrativefigures.

FIG. 1 illustrates a reactor system in accordance with at least oneexemplary embodiment of the present disclosure.

FIG. 2 illustrates a flange assembly in accordance with at least oneexemplary embodiment of the disclosure.

FIG. 3 illustrates a cross-sectional view of a flange assembly inaccordance with at least one exemplary embodiment of the disclosure.

FIG. 4 illustrates another cross-sectional view of a flange assembly inaccordance with at least one exemplary embodiment of the disclosure.

FIGS. 5 and 6 illustrate additional views of a flange assembly inaccordance with at least one exemplary embodiment of the disclosure.

FIGS. 7, 8 and 9 illustrate cross-sectional views of a flange accordancewith at least one embodiment of the disclosure.

FIG. 10 illustrates an additional view of a flange in accordance with atleast one embodiment of the disclosure.

FIGS. 11 and 12 illustrate cooling tubes in accordance with illustrativeexamples of the disclosure.

FIG. 13 illustrates another view of a flange assembly in accordance withat least one embodiment of the disclosure.

FIG. 14 illustrates a view of a flange assembly and a heated manifold inaccordance with at least one embodiment of the disclosure.

It will be appreciated that elements in the figures are illustrated forsimplicity and clarity and have not necessarily been drawn to scale. Forexample, the dimensions of some of the elements in the figures may beexaggerated relative to other elements to help to improve theunderstanding of illustrated embodiments of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE DISCLOSURE

The description of exemplary embodiments provided below is merelyexemplary and is intended for purposes of illustration only; thefollowing description is not intended to limit the scope of thedisclosure or the claims. Moreover, recitation of multiple embodimentshaving stated features is not intended to exclude other embodimentshaving additional features or other embodiments incorporating differentcombinations of the stated features.

The present disclosure generally relates to flanges and flangeassemblies suitable for coupling to a reaction chamber, to reactorsystems including the flange(s) and/or flange assemblies, and to methodsof using the flanges, flange assemblies, and reactor systems.

The reactor systems including a one or more flanges and/or flangeassemblies as described herein can be used to process substrates, suchas semiconductor wafers, in gas-phase reactors. By way of examples, thesystems described herein can be used to form or grow epitaxial layers(e.g., two component and/or doped semiconductor layers) on a surface ofa substrate.

As used herein, a “substrate” refers to any material having a surfaceonto which material can be deposited. A substrate may include a bulkmaterial such as silicon (e.g., single crystal silicon) or may includeone or more layers overlying the bulk material. Further, the substratemay include various topologies, such as trenches, vias, lines, and thelike formed within or on at least a portion of a layer of the substrate.

As set forth in more detail below, various sections of theflanges/flange assemblies can be cooled and other sections of theflanges/flange assemblies can be heated. This allows operation ofreactors and reactor systems including such flanges and flangeassemblies to operate at elevated temperatures (e.g., from about 150° C.to about 200° C. or about 180° C. to about 200° C.), while mitigatingresidue buildup (e.g., from reaction with or condensation of precursorsand/or reaction byproducts within the reaction chamber) on the flange orassembly that might otherwise occur. By reducing the residue buildup, amean time to maintenance of the reactor system or components thereof canbe reduced. In addition, safety risks associated with the residuebuildup are reduced. This may become increasingly important when usingprecursors that are liquid or solid at standard room temperature andpressure. The flanges and assemblies as described herein can providecooling proximate a sealing member to mitigate deterioration of thesealing member that might otherwise occur. The cooling can be localizedproximate the sealing members and/or the heating can be proximate aninner (reaction chamber side) surface of the flange and away from thesealing member. The flanges and flange assemblies described herein maybe particularly useful in epitaxial reactors (e.g., hot-walledreactors), such as the Intrepid or Epsilon reactors available from ASM.

Turning now to the figures, FIG. 1 illustrates an exemplary reactorsystem 100. Reactor system 100 can be used for a variety ofapplications, such as, for example, chemical vapor deposition (CVD),plasma-enhanced CVD (PECVD), atomic layer deposition (ALD), cleanprocesses, etch processes, and the like. Although exemplary embodimentsare described below in connection with epitaxial reactor systems, theembodiments and the invention are not so limited, unless statedotherwise.

In the illustrated example, reactor system 100 includes a first flangeassembly 102, a second flange assembly 104, a reaction chamber 106, anexhaust source 108, and a controller 110. Reactor system 100 can beconfigured as a cross flow, hot-wall epitaxial reactor system. Exemplaryreactor systems including a horizontal flow reactor are available fromASM.

During operation of reactor system 100, substrates, such assemiconductor wafers, (not illustrated) are transferred from, e.g., asubstrate handling system (not illustrated), to reaction chamber 106.Once substrate(s) are transferred to reaction chamber 106, one or moregasses, such as precursors, dopants, carrier gasses, and/or purge gassesare introduced into reaction chamber 106 via second flange assembly 104.Any unreacted gasses and/or reaction byproducts exit reaction chamber106 and flow through first flange assembly 102 toward exhaust source108. Controller 110 can be used to control a cooling and/or heating offlange assembly 102 and/or 104 to, e.g., control heaters embeddedtherein and/or control cooling (e.g., by controlling a flowrate ofcooling liquid, such as water (e.g., filtered house water at roomtemperature) provided to flange assemblies 102, 104). Exemplaryflowrates can range from, for example, about 0.5 L/min. to about 1.2L/min.

FIGS. 2-13 illustrate an exemplary first flange assembly 102 andportions thereof in more detail. First flange assembly 102 includes a(e.g., first) flange 202, heaters 204, 206, 302 and 402, 404, andcooling channels 304-310 to receive cooling fluid, such as water. Firstflange assembly 102 also includes a first sealing member 312 to form aseal with reaction chamber 106 and a second sealing member 314 to form aseal with a cover plate 208. First flange assembly 102 also includes oneor more thermocouples 210-216 to measure temperatures at variouslocations within first flange assembly 102. As described in more detailbelow, the temperature information from one or more thermocouples210-216 can be used to provide information to controller 110 and/or tocontrol heaters and/or cooling to first flange assembly 102. Firstflange assembly 102 can also include one or more heater retainers 218,317, 319 to retain the heaters in place.

Flange 202 can be formed of any suitable material, such as stainlesssteel, and Hastelloy. Flange 202 includes a first surface 220 forcoupling to a reactor or reaction chamber, a second surface 222 forcoupling to cover plate 208, and an opening 224 between first surface220 and second surface 222. First surface 220 includes a recess 316 toreceive sealing member 312. Similarly, second surface 222 includes arecess 318 to receive sealing member 314. Further, flange 202 includescooling channels 304-310 formed therein. Cooling channels 304-310 can beconfigured to receive cooling fluid directly or via tubes (e.g., pipes)1102, 1104, 1202, and 1204, illustrated in FIGS. 11 and 12. Flange 202also includes recesses 506, 508, 406, 408, and 320 to receive one ormore heaters 204, 206, 302 and 402, 404. Forming recesses within flange202 to receive heaters 204, 206, 302 and 402, 404 allows for placementof the heaters near an interior (reaction chamber side) of flange202—e.g., near first surface 220. Similarly, forming cooling channels304-310 within flange 202 allows for placement of the cooling channelsproximate sealing members 312, 314. Further, by using recesses andretainers, as illustrated, heaters 204, 206, 302 and 402, 404 can beeasily removed and replaced when desired-without removing flange 202from reactor system 100, while allowing for placement of the heaters atdesired locations within flange 202. As illustrated, flange 202 can alsoinclude one or more recesses to receive thermocouples 210-216 and/orretaining devices (e.g., screws or bolts). The recesses described hereincan machined—i.e., cut out of material used to form flange 202.Machining, rather than simply drilling holes for the heaters can allowfor, for example, desired placement and of the heaters within flange202.

Heaters 204, 206, 302 and 402, 404 can be formed of any suitablematerial. By way of examples, heaters 204, 206, 302 and 402, 404 areresistive heaters, such as those available from SAKAGUCHI E.H. VOC CORP,and Watlow. Exemplary heaters have a power of about 500 to about 1000 orabout 700 Watts. Although not illustrated, heaters 204, 206, 302 and402, 404 can include cables to couple to controller 110 and/or to asuitable power source, which can be included as part of controller 110or separate therefrom. By way of examples, heaters 204, 206, 302 and402, 404 can be configured to heat areas of flange 202 to a temperatureof about 150 to about 200° C. or about 180 to about 200° C.

First sealing member 312 and second sealing member 314 can be formed ofresilient material, such as heat-resistant resilient material, such assilicone, Kalrez, or Viton.

Thermocouples 210-216 can include any suitable thermocouple. Exemplarythermocouples suitable for use as thermocouples 210-216 are availablefrom OMEGA Engineering.

Cover plate 208 and/or heater retainers 218, 317, 319 can be formed ofthe same material as flange 202. By way of example, cover plate 208 andheater retainers 218, 317, 319 are formed of stainless steel.

First flange assembly 102 can also include a cover 502 surrounding aportion of an outlet 504. Cover 502 can be formed of the same or similarmaterial as flange 202.

Turning now to FIGS. 8 and 9, cooling channels 304-310 are illustratedin greater detail. FIG. 8 illustrates a bottom cross-sectional view offlange 202, illustrating cooling channels 308, 310. Similarly, FIG. 9illustrates a top cross-sectional view of flange 202, illustratingcooling channels 304, 306. While a diameter or similar cross-sectionaldimension for cooling channels 304-310 can vary in accordance withdesign considerations, in accordance with some examples of thedisclosure, the cross-sectional dimension ranges from about 400 mm toabout 500 mm, or about 15 mm to about 35 mm. In accordance with examplesof the disclosure, cooling channels and flow rate controllers 112, 114can be configured to maintain a temperature of sections of flangeproximate resilient seal 312, 314 of about 80 to about 120° C. or about100 to about 120° C. Although illustrated in the supply line, flow ratecontrollers 112, 114 can additionally or alternatively be placed withinthe return line(s).

As illustrated, cooling channels and pipes 1102, 1104, 1202, 1204 canform a loop, such that a single inlet 1206 and a single outlet 1208provide a continuous loop of coolant proximate one or more of resilientseal 312, 314. Further, as illustrated, in for example, FIGS. 2, 5, 6and 13, portions of the continuous loop can include vertical sections1302-1308 that reside outside flange 202. However, in accordance withother examples, such vertical sections could be included within—e.g.,embedded within—flange 202.

FIG. 14 illustrates second flange assembly 104 and an injection manifold1402, in accordance with further examples of the disclosure. Secondflange assembly 104 includes a (e.g., second) flange 1404, heaters 1406,1408, and cooling channels, illustrated as channels 1410, 1412, whichcan be the same or similar to channels 304-310. Second flange assembly104 also includes a first sealing member 1414 to form a seal withreaction chamber 106 and a second sealing member (not illustrated, butwhich can be the same or similar to any of sealing members 1414, 312,314) to form a seal with a gate valve (not illustrated). Second flangeassembly 104 also includes one or more thermocouples 1416 to measuretemperatures at various locations within second flange assembly 104. Thetemperature information from one or more thermocouples 1416 can be usedto provide information to controller 110 and/or to control heatersand/or cooling to second flange assembly 104. Second flange assembly 104can also include one or more heater retainers as described herein.

Flange 1404 can be formed of any suitable material, such as stainlesssteel. Similar to flange 202, flange 1404 includes a first surface 1418for coupling to a reactor or reaction chamber 106, a second surface 1420for coupling to cover plate and/or a gate valve, and an opening 1422between first surface 1418 and second surface 1420. First surface 1418includes a recess 1424 to receive sealing member 1414. Similarly, secondsurface 1420 can include a recess to receive another sealing member(e.g., the same or similar to sealing member 314). Further, flange 1414includes cooling channels 1410, 1412 formed therein. Cooling channels1410, 1412 can be configured to receive cooling fluid directly or viatubes (e.g., pipes), such as tubes 1102, 1104, 1202, and 1204,illustrated in FIGS. 11 and 12. Flange 1404 also includes recesses 1426,and 1428 to receive one or more heaters 1406 and 1408. Flange 1404 canalso include various conduits configured to keep reactants/precursorsseparated, until such gasses reach reaction chamber 106. An exemplaryflange conduit configuration is disclosed in U.S. application Ser. No.14/218,690, filed Mar. 18, 2014 and entitled GAS DISTRIBUTION SYSTEM,REACTOR INCLUDING THE SYSTEM, AND METHODS OF USING THE SAME, thecontents of which are hereby incorporated herein by reference, to theextent such contents do not conflict with the present disclosure.

Injection manifold 1402 is configured to provide one or more precursors,reactants, and purge and/or carrier gasses to reaction chamber 106. Anexemplary injection manifold is described in U.S. application Ser. No.15/997,445, filed Jun. 4, 2018 and entitled GAS DISTRIBUTION SYSTEM ANDREACTOR SYSTEM INCLUDING SAME, the contents of which are herebyincorporated herein by reference, to the extent such contents do notconflict with the present disclosure. Lines 1430 and 1432 can be heated(e.g., using flexible (e.g., silicone) heater tape) to maintain gaswithin the lines at a desired temperature—e.g., to prevent or mitigatecondensation of the gas. Additionally or alternatively, a heater 1434can be provided around and/or proximate injection manifold 1402 toprevent and/or mitigate condensation of gas within injection manifold1402.

Heaters 1406, 1408 and cooling channels 1410, 1412 can be the same orsimilar to those described above in connection with FIGS. 2-13 and canhave the same or similar dimensions. Similarly, one or morethermocouples 1416 can be the same or similar to the thermocouplesdescribed above.

Reaction chamber 106 can be formed of, for example quartz. Exemplaryoperating pressures within reaction chamber 106 can range from about 10Torr to about atmospheric (˜760 Torr).

Exhaust source 108 can include, for example, one or more vacuum sources.Exemplary vacuum sources include one or more dry vacuum pumps and/or oneor more turbomolecular pumps.

Controller 110 can be configured to perform various functions and/orsteps as described herein. Controller 110 can include one ormicroprocessors, memory elements, and/or switching elements to performthe various functions. Although illustrated as a single unit, controller110 can alternatively comprise multiple devices. By way of examples,controller can be used to control flow of coolant in and/or out ofcooling tube (e.g., tubes 1102, 1104, 1202, 1204) and/or one or more(e.g., all) of the cooling channels described herein. Additionally oralternatively, controller can be used to control heaters, such as one ormore of the heaters described herein. In particular, controller 110 canbe configured to provide desired cooling to first flange assembly 102and/or second flange assembly 104 by controlling an amount of coolant(e.g., water) flow into the respective tubes or channels. Additionallyor alternatively, controller 110 can be used to control power to the(e.g., resistive) heaters. In accordance with various examples of thedisclosure, controller 110 is or includes aproportional-integral-derivative (PID) controller, which allowsclosed-loop control of the heating and/or cooling of the respectiveflange assemblies or sections thereof. Controller 110 can also becoupled to thermocouples (not separately illustrated) within reactionchamber 106.

Various valves (e.g., water flow valves 112, 114) described herein caninclude solenoid valves.

In accordance with further embodiments of the disclosure, variouscombinations of reaction chamber 106, heaters in first flange assembly102, heater in second flange assembly 104, cooling fluid supplied tofirst flange assembly 102, and/or cooling fluid supplied to secondflange assembly 104 can be manipulated to mitigate deposition ofmaterial onto a surface of first flange assembly 102 and/or secondflange assembly 104. For example, a power of one or more heaters can beset to a desired level and a temperature of the flange assemblies can becontrolled by manipulating an amount of cooling water supplied to arespective flange assembly. Alternatively, the flowrate of the coolantcan be set and the power to the heaters can be manipulated. Or, acombination of power to the heaters, flowrate of coolant, and/orreaction chamber temperature can be manipulated. Additionally oralternatively, the set point temperatures, flowrates, and/or powers canbe changed between process steps for processes within reaction chamber106.

Although exemplary embodiments of the present disclosure are set forthherein, it should be appreciated that the disclosure is not so limited.For example, although the flanges, flange assemblies, and reactorsystems are described in connection with various specificconfigurations, the disclosure is not necessarily limited to theseexamples. Various modifications, variations, and enhancements of thesystem and method set forth herein may be made without departing fromthe spirit and scope of the present disclosure.

The subject matter of the present disclosure includes all novel andnonobvious combinations and subcombinations of the various systems,components, and configurations, and other features, functions, acts,and/or properties disclosed herein, as well as any and all equivalentsthereof.

We claim:
 1. A flange assembly comprising: a flange comprising: a firstsurface for coupling to a reactor; an opposing second surface; and anopening between the first surface and the second surface; at least oneheater; and at least one cooling channel.
 2. The flange assembly ofclaim 1, wherein the at least heater is embedded within the flange. 3.The flange assembly of claim 1, wherein the at least cooling channel isembedded within the flange.
 4. The flange assembly of claim 1, whereinthe first surface comprises a recess to receive a sealing member.
 5. Theflange assembly of claim 4, wherein the at least cooling channel isproximate the recess.
 6. The flange assembly of claim 1, wherein thesecond surface comprises a recess to receive a sealing member.
 7. Theflange assembly of claim 6, wherein the at least cooling channel isproximate the recess.
 8. The flange assembly of claim 1, wherein theflange further comprises an exhaust outlet.
 9. The flange assembly ofclaim 8, wherein the at least heater is proximate the exhaust outlet.10. The flange assembly of claim 9, wherein the flange assemblycomprises at least two heaters proximate the exhaust outlet.
 11. Theflange assembly of claim 1, wherein the flange comprises at least twoheaters on opposing sides of the opening.
 12. The flange assembly ofclaim 1, wherein the flange comprises at least four heaters proximatethe opening.
 13. The flange assembly of claim 1, wherein the flangefurther comprises one or more openings to receive one or morethermocouples.
 14. The flange assembly of claim 1, further comprising acover plate.
 15. The flange assembly of claim 1, further comprising oneor more heater retainers.
 16. A reactor system comprising the flangeassembly of claim
 1. 17. A flange comprising: a first surface forcoupling to a reactor; an opposing second surface; an opening betweenthe first surface and the second surface; at least one recess to receivea heater; and at least one cooling channel.
 18. The flange of claim 17,wherein the first surface comprises a recess to receive a sealingmember.
 19. The flange of claim 17, wherein the second surface comprisesa recess to receive a sealing member.
 20. The flange of claim 17,further comprising an exhaust outlet, wherein at least one of the atleast one recess to receive a heater is proximate the exhaust outlet.21. The flange of claim 17, wherein the flange comprises at least tworecess, each of the at least two recesses configured to receive one ormore heaters, the at least two recesses proximate the opening.